The present invention relates generally to a fraction collection system, and more particularly to an automated system permitting separation, enrichment and fractionation of sub-cellular particles.
Characterization of biological materials, such as biological molecules and organelles, has become increasingly important. Precise characterization of these materials can lead to novel drug therapies for treating disease, as well as to a greater understanding of the mechanisms underlying many diseases. Many biological materials exhibit a buoyant density that can be used to distinguish them from other materials. Such materials can be separated using density gradients and procedures such as differential centrifugation. For example, lipoproteins are composed of varying amounts of proteins and lipids. They differ not only by size and electrophoretic mobility, but also by buoyant density. Thus, in addition to other techniques available for separating, identifying, and classifying lipoproteins, density-gradient ultracentrifugation may be used. Such methodologies are complicated and time consuming particularly when minute fractions of large samples are being analyzed. Thus, there is a need for an automated method of isolating biological materials that can be used with smaller or larger samples and a method that is capable of segregating dilute materials from large samples.